This invention is generally directed to an apparatus for mounting a wheel on a vehicle such as a trailer or the like. More particularly, the invention contemplates a novel valve or venting structure which prevents the build-up of pressure within the wheel mounting apparatus.
Apparatus for mounting wheels on trailers are well-known in the art. Such apparatuses generally include a hollow axle and wheel bearings lubricated by a bath of oil or light grease contained in a cavity defined by a hollow wheel hub. A slip ring type seal is provided between the wheel hub and the axle to prevent oil from leaking out at one end of the wheel hub and an end cap is provided at the other end of the wheel hub in order to contain the oil therein.
A small hole or a sintered metal plug is provided through the end cap for preventing the build-up of pressure formed under heating conditions of operations within the wheel hub which might force oil through the slip ring seal. The small hole or sintered plug, however, are subject to being blocked with grease or oil so as to become inoperative.
The present invention presents a novel valve or venting structure for an axle which is used to mount a wheel on a vehicle such as a trailer that is intended to overcome this problem and other inherent problems in the prior art as well as to present several other advantages and improvements.